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Evaluation Of High Pressure Pretreatment For Enhancing The Drying Rate Of Selected Fruits And VegetablesYucel, Umut 01 September 2006 (has links) (PDF)
Drying is a process of moisture removal due to simultaneous heat and mass transfer. High hydrostatic pressure (HHP) processing subjects liquid and solid foods, with or without packaging, to pressures between 100 and 800 MPa. The application of HHP affects cell wall structures, leaving the cells more permeable, facilitating the diffusion and providing higher drying rates.
In this study, two variety of apples, i.e. Amasya and red delicious, green beans and carrots were pretreated with HHP at different pressure-time-temperature combinations (100 &ndash / 300 MPa for 5 &ndash / 45 min at 20 and 35° / C) prior to drying. Hot air drying experiments were carried at different temperatures (27, 45, 65, and 85° / C) and air velocity of 0.4 and 0.8 m/s. To obtain the drying data, samples were subjected to hot air drying under constant external conditions. The applicability of 14 kinetic models selected from the literature for the drying of fruits and vegetables was determined by appropriate statistical analyses procedures.
Improving the drying conditions by increasing the drying temperature generally masked the effect of HHP pretreatment on drying rate. Only for green beans, HHP treatments at 20° / C decreased the drying rate. Generally pressures of HHP pretreatment higher than 100 MPa caused cell permeabilization resulted in higher drying rates for apples and carrots. Among the 14 models, modified Page model for apples, and modified Page and two term exponential models for green beans and carrots were found to best explain the drying behaviors.
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Ovoce a zelenina ve výživě člověka. / Fruits and vegetables in food.PROCHÁZKOVÁ, Michaela January 2008 (has links)
This diploma thesis is focused on the theme fruit and vegetable in human´s nutrition. The theoretical part describes the nutrition in general, its parts and vegetable and fruit. Methodical part creates question-form on this theme with evaluation.
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Avaliação microbiológica da alface (Lactuca sativa) em sistema de cultivo hidropônico e no solo, correlacionando os microrganismos isolados com os encontrados em toxinfecções alimentares em municípios da região Noroeste de São Paulo - SP /Paiva, Jeferson Leandro de. January 2011 (has links)
Orientador: Fernando Leite Hoffmann / Banca: Vanildo Luiz Del Bianchi / Banca: Maria Luiza Silva Fazio / Resumo: A coleta da alface (Lactuca sativa) e da água de manejo foi realizada no local de cultivo, tanto pelo método de hidroponia (CH) como pelo tradicional no solo (CT) em estabelecimentos hortifrutigranjeiros e restaurante (R) localizados em cidades da região noroeste paulista. As vinte e cinco amostras analisadas foram coletadas em dias alternados, sendo cinco amostras de cada local. As análises foram realizadas com objetivo de verificar se a origem das toxinfecções alimentares envolvendo pratos que contenham alface é proveniente de microrganismos do local de produção das hortaliças. Os resultados obtidos possibilitaram analisar a ocorrência de contaminação cruzada com outras hortaliças enxaguadas no mesmo tonel e comparar o índice de contaminação dos dois tipos de sistema de cultivo. As análises microbiológicas seguiram as metodologias tradicionais descritas por Silva; Junqueira e Silveira (2001), de acordo com a American Public Health Association. Os resultados das análises mostraram grande variação na contagem dos microrganismos. Nas amostras de alface 92% (23) apresentaram crescimento de coliformes totais variando entre 0,4 a ≥240 NMP/g dos quais 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) apresentaram coliformes termotolerantes variando entre 0,9 a 46 NMP/g, sendo 24% (6) CT e 8% (2) R; 36% (9) apresentaram Staphylococcus coagulase positiva, onde 12% (3) apresentaram crescimento acima dos parâmetros estabelecidos 5x103 UFC/g, sendo 4% (1) CT e 8% (2) CH. Todas as amostras positivas para coliformes termotolerantes estão dentro dos limites estabelecidos pela ANVISA (BRASL, 2001) de 102 UFC/g. Nenhuma amostra foi positiva para Salmonella spp, atendendo os parâmetros estabelecidos pela ANVISA (BRASIL, 2001) de ausência em 25g do produto. Os resultados obtidos nas análises da água foram de 95% (19) apresentando coliformes totais variando... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The collect of lettuce (Lactuca sativa) and the water used to grow it was made in the local of its cultivation through both hydroponics (CH) and the traditional in the soil (CT) methods in fruit/vegetable/poultry stores and restaurants (R) localized in the cities of the Paulista northwest region. The twenty-five samples analyzed were collected in alternate days, being five samples from each place. The analyses were carried out with the target to check if the origin of food toxinfection involving dishes that have lettuce is from microorganisms of the local where the vegetables are cultivated. The results obtained enabled to analyze the occurrence of contamination crossed with other vegetables rinsed in the same cask. Besides, to compare the rate of contamination of the two kinds of cultivation. The microbiological analyses followed the traditional methodologies written by Silva; Junqueira e Silveira, (2001), according to the American Public Health Association. The results of the analyses showed a great variation on the count of the microorganisms. In the lettuce samples 92% (23) presented growing of total coliforms varying between 0, 4 to ≥ 240 NMP/g from which 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) presented thermotolerant coliforms varying between 0,9 to 46 NMPg, being 24% (6) CT and 8% (2) R. 36% (9) presented coagulase-positive Staphylococcus, where 12% (3) presented growing over the parameters established 5x103 UFC/g, being 4% (1) CT and 8% (2) CH. All the positive samples for thermotolerant coliforms are inside the limits established by ANVISA (BRASIL, 2001) of 102 UFC/g. No sample was positive for Salmonella spp, attending the parameters established by ANVISA (BRASIL, 2001) of absence in 15g of the product. The results obtained from the analyses of the water were from 95% (19) presented total coliforms varying between... (Complete abstract click electronic access below) / Mestre
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Avaliação microbiológica da alface (Lactuca sativa) em sistema de cultivo hidropônico e no solo, correlacionando os microrganismos isolados com os encontrados em toxinfecções alimentares em municípios da região Noroeste de São Paulo - SPPaiva, Jeferson Leandro de [UNESP] 28 April 2011 (has links) (PDF)
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000642743.pdf: 1481069 bytes, checksum: 9eadf983610de6546b09d759783f8618 (MD5) / A coleta da alface (Lactuca sativa) e da água de manejo foi realizada no local de cultivo, tanto pelo método de hidroponia (CH) como pelo tradicional no solo (CT) em estabelecimentos hortifrutigranjeiros e restaurante (R) localizados em cidades da região noroeste paulista. As vinte e cinco amostras analisadas foram coletadas em dias alternados, sendo cinco amostras de cada local. As análises foram realizadas com objetivo de verificar se a origem das toxinfecções alimentares envolvendo pratos que contenham alface é proveniente de microrganismos do local de produção das hortaliças. Os resultados obtidos possibilitaram analisar a ocorrência de contaminação cruzada com outras hortaliças enxaguadas no mesmo tonel e comparar o índice de contaminação dos dois tipos de sistema de cultivo. As análises microbiológicas seguiram as metodologias tradicionais descritas por Silva; Junqueira e Silveira (2001), de acordo com a American Public Health Association. Os resultados das análises mostraram grande variação na contagem dos microrganismos. Nas amostras de alface 92% (23) apresentaram crescimento de coliformes totais variando entre 0,4 a ≥240 NMP/g dos quais 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) apresentaram coliformes termotolerantes variando entre 0,9 a 46 NMP/g, sendo 24% (6) CT e 8% (2) R; 36% (9) apresentaram Staphylococcus coagulase positiva, onde 12% (3) apresentaram crescimento acima dos parâmetros estabelecidos 5x103 UFC/g, sendo 4% (1) CT e 8% (2) CH. Todas as amostras positivas para coliformes termotolerantes estão dentro dos limites estabelecidos pela ANVISA (BRASL, 2001) de 102 UFC/g. Nenhuma amostra foi positiva para Salmonella spp, atendendo os parâmetros estabelecidos pela ANVISA (BRASIL, 2001) de ausência em 25g do produto. Os resultados obtidos nas análises da água foram de 95% (19) apresentando coliformes totais variando... / The collect of lettuce (Lactuca sativa) and the water used to grow it was made in the local of its cultivation through both hydroponics (CH) and the traditional in the soil (CT) methods in fruit/vegetable/poultry stores and restaurants (R) localized in the cities of the Paulista northwest region. The twenty-five samples analyzed were collected in alternate days, being five samples from each place. The analyses were carried out with the target to check if the origin of food toxinfection involving dishes that have lettuce is from microorganisms of the local where the vegetables are cultivated. The results obtained enabled to analyze the occurrence of contamination crossed with other vegetables rinsed in the same cask. Besides, to compare the rate of contamination of the two kinds of cultivation. The microbiological analyses followed the traditional methodologies written by Silva; Junqueira e Silveira, (2001), according to the American Public Health Association. The results of the analyses showed a great variation on the count of the microorganisms. In the lettuce samples 92% (23) presented growing of total coliforms varying between 0, 4 to ≥ 240 NMP/g from which 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) presented thermotolerant coliforms varying between 0,9 to 46 NMPg, being 24% (6) CT and 8% (2) R. 36% (9) presented coagulase-positive Staphylococcus, where 12% (3) presented growing over the parameters established 5x103 UFC/g, being 4% (1) CT and 8% (2) CH. All the positive samples for thermotolerant coliforms are inside the limits established by ANVISA (BRASIL, 2001) of 102 UFC/g. No sample was positive for Salmonella spp, attending the parameters established by ANVISA (BRASIL, 2001) of absence in 15g of the product. The results obtained from the analyses of the water were from 95% (19) presented total coliforms varying between... (Complete abstract click electronic access below)
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